Gas mixing device



1934- E. T. LARKIN GAS MIXING DEVICE Filed April 14, 1932 2 Sheets-Sheetl Feb. 20, 1934. ARK|N 1,947,603

GAS MIXING DEVICE Filed April 14, 1932 2 Sheet-Sheet 2 if if PatentedFeb. 20, 1934 r 1,947,603

UNETED STATES PATENT OFFHJE GAS MIXING DEVICE Elwood T. Larkin,Eggertsville, N, Y., assignor to Charles A. Criqui, Buffalo, N. Y.

Application April'li, 1932. Serial No. 605,219

11 Claims. (Cl. 48180) This invention relates to devices for mixingwherever a mixing of two gases is desired in two gases in desiredproportions to each other, definite proportions. as may, for example, benecessary in connection In the accompanying drawings: 1 g with internalcombustion engines or other de- Fig. 1 is a side elevation of aninternal 'cohi- I vices to which gas mixtures may be fed. bustion enginehaving a gas mixing device em- 60 Gas mixing devices, as heretoforemade, have bodying this invention applied thereto; 7 been adjustable tooperate only within a limited F 2 iS an end V w Of the mixing V lverange of proportions. Consequently, if a proon an enlarged S portion oithe two gases beyond such range Fig. 3 is a transverse sectionalelevation was required, another mixing device or valve thereof, on line33, Fig. 6;

had to be supplied. When devices of this kind Fig. l is a transversesectional elevation thereare used in connection with internal combustionof, on line 4--4, Fig. 7

engines, these devices are sometimes required to Fig- 5 is a lo a S conal elevation operate on gases difiering widely in quality. It of thegas pressure regulating device shown is also desirable with engines ofthis kind to in Fig. 76

provide means whereby an engine can be Figs. 6 and 7 are longitudinal,central secquickly changed over to operate on liquid i tional'elevations of the mixing valve, showing stead of gaseous fuel, as may,for example, be he Pa the e in d f ent p sitions.

the case where an engine is operating on a gas A represents an internalCombustion supply which is not available at all times. which may be ofany Su a Construction, and 76 The objects of this invention are toprovide which has a a inlet pa a te Which a 06ma gas mixing device bymeans of which a wide bustihle mixture is to be pp B ep evariation inthe proportions of two gases may sents in gen l a gas mixing v Which hbeobtained and with which one f th gas plies a combustible mixture to thegas inlet supplies may be entirely interrupted; also to Passage 0 0f theengine- Air is ordinarily ad- 35 proved construction; also to provide agas mixprovide a device of this kind, which is so conmitted t0 themixing Valve B ug an i et structed as to produce a constant and accuductelbow 10 Containing a Choke Valve 1, rately proportioned mixture ofgases under Operable by means of a Crank arm different rates f upply fthe gases; 12, Fig. 1. C represents a carburetorywhi'ch also to providea gas mixing device of this kind may be used when the engine is run ongas, for mixing air and gas and in which the gas the carburetor andconnections shown in broken is supplied at a pressure not Substantiallylines in Fig. rare entirely detached so that air ceeding atmosphericpressure; also to provide a for mlxmg w gas can enter the Open end gasmixing valve with a throttle valve of imof h an Intake duct 15represents the gas inlet duct of the mixing valve B to which gas may beconducted through a passage 16 and connected with an accumulator orreservoir 17 containing the gas at a reduced pressure, the gasoriginally being received under pressure through a pipe 18 leading to apressure reducing valve D.

ing valve with means for quickly and accu rately adjusting the valve forthe proportions of the two gases desired; also to provide a valve ofthis kind with improved means for locking the same in its adjustedposition; also to provide a valve of this kind with means for indli Themixing valve itself, in the particular concafltmg when the Valve 15producmg struction illustrated, has a substantially cylinm of thedesired P also to drical housing 20 formed at its upper side of 5 vide avalve of thls kmd i f deflect for its cylindrical wall with a dischargepassage 21 efiectmg a moire cempleie mlxmg the two and a flange 22arranged about this passage also commence of gas serves to connect themixing valve with the air mixing devices of this kind in other respectsintake passage a of t engine The pipe or heremaftel' speclfiedgas duct15 may be connected with a threaded 50 The gas mixin deYice isillustrated in the nipple 24 formed integrally on a side of the a ompanydrawings r u in connection mixing valve B and the gas, in theconstruction with internal combustion engines, but it Will be shown,enters the housing 20 of the valve understood that it is not intended torethrough an opening 25 therein, a passage 26 in strict the device foruse in connection with the valve housing connecting the threaded nip- 5engines since obviously the device can be used ple 24 with the opening25. The ends of the cylindrical housing 20 may be closed by end coversor plates 2? and 23 secured in any suitable manner to the cylindricalhousing, for example, by means of bolts or screws 29, Fig. 2. 30represents the airintake passage or opening in the cylindrical housing20 through which air enters the interior of the mixing valve from theinlet duct 10.

lhe combustible gases which may be used in connection with internalcombustion engines differ greatly in quality, some of these gases beingas low as B. t. u.s per cubic foot, whereas other gases contain as muchas 1500 B. t. u.s per cubic feet. In order to provide for the desiredratio of the two gases entering into the housing as, means are providedfor constricting one of the two inlet openings while enlarging theother. In the construction shown for this purpose, a proportioningmember 32 is provided which is in the form of a cylinder arranged to beadiusted lengthwise within the cylindrical housing so. Thisproportioning member or cylinder is provided with an air opening 33 anda gas opening 34. The air and gas openings 33 and 34 are approximatelyof the same sizes respectively as the air passage 30 and of the gasopening 25 in the valve housing, but the openings 33 and 34 are soarranged that when the opening 33 is in full registration with theair'inlet passage 30 so as to admit the maximum air, the gas opening 34will be entirely or almost entirely out of registration with the gasopening 25 so that the passage of gas into the mixing valve isinterrupted, as shown in Fig. 7. When the proportioning member 82 ismoved to the left, the size of the air passage through the inlet 30 andopening 33 is reduced and a corresponding increase results in the sizeof the gas opening, in proportion to the extent to which the member327is moved to the left, Fig. 6 showing the gas opening almostunobstructed and the air passage reduced to almost half of its maximumsize. The proportioning member is provided in its opposite side with arelatively large discharge opening 35 which registers with the dischargepassage 21 during all positions of the proportioning member 32, so thatthe discharge passage for the mixture is not interrupted or decreased insize in any position of the proportioning member.

Any suitable or desired means may be employed for adjusting the positionof the proportioning member or valve 32. In the particular constructionshown, a screw threaded stem or bolt 37 is secured at its inner end tothe proportioning member 32, for example, by means of a screw or pin 38,and extends out through the end cover or plate 28 at one side of themixing valve. This screw 3'? engages an internally threaded sleeve 39having a hand wheel 40 secured to the outer end thereof, for exam ple,by means of a threaded engagement with the sleeve 39 and a pin 41, andthe sleeve 39 has at its inner end an outwardly extending flange -orprojection 42 engaging at its inner side on an inwardly extending flangeor annular bead 43 of the end or cover plate 23. In order to hold thesleeve 39 against endwise movement during the turning of the same, agland nut 45 is provided having a central bore or aperture into whichthe sleeve 39 fits snugly. The outer surface of this gland nut isthreaded and engages a correspondingly internally threaded boss 46formed on the end cover member 28. The flange 42 of the sleeve 39engages the inner end of the gland nut 45 so that outward movement ofthe sleeve is prevented by the gland nut. Consequently, by turning thesleeve 39 in either direction, a corresponding movement of theproportioning member 32 results. When the proportioning member has beenadjusted to the desired position, the gland nut 45 may be turned in adirection to clamp the outwardly extending flange 4-2 of the sleeve 39against the inwardly extending flange 43 of the end cover member 28, andthus secure the sleeve 39 against turning, which in turn prevents anychange in adjustment of the proportioning member 32 until the gland nutis again released. Any other means for adjusting the proportioningmember and for locking the same in its adjusted position may beemployed, if desired.

The mixing valve is also provided with a throttle which is arranged toact on the incoming air and gas passages to vary the amount of air andgas admitted through these openings, and thus to control the speed ofthe engine when the mixing device is used connection with an engine. Thethrottle valve, in the construction shown, includes a substantiallysemicylindrical portion 48 adapted to fit Within the cylindricalprcportioning member 32, and is also provided with radially extendingend webs or parts 49 and 50, preferably formed integrally with thecylindrical portion 48 and suitably secured to a central shaft 51, forexample, by

means of taper pins 52. This shaft is journalled in bearings 54 suitablyarranged in the opposite end cover members 2! and 28, roller bearingsbeing shown in the construction illustrated.

The semi-cylindrical portion 43 of the throttle valve is provided withan opening 56 which is adapted to register with the air passage 30 inthe cylindrical member 26 and an opening 57 adapted to register with thegas opening 25 in the housing 20. Consequently, it will be obvious thatby turning the shaft 51 and the throttle valve in either direction fromthe position shown in Fig. 4, the passages for air and gas will bedecreased, and the decrease in these passages will be in the sameproportion in both passages. The turning of the throttle member isentirely independent of the adjustment of the proportioning member 32,so that by changing the position of the throttle member, the proportionof gases in the mixture discharged from the mixing valve will not bechanged. By means of the arrangement of the throttle member asdescribed, the suction of the engine acting on the semi-cylindricalthrottle member when the same is partly closed, will tend to move thethrottle member out of contact with the cylindrical surface of theproportioning member 32, so that friction between these two members isavoided. This is particularly desirable when the operation of thethrottle member is controlledby a governor which has very little powerby means of which the throttle valve is turned. The end webs 49 and 50,in addition to supporting the throttle valve from the shaft 51, also actas deflectors for controlling or directing the flow of gas through theinterior or" the valve, keeping the gas from flowing into the endportions of the mixing valve, and thereby reducing the resistance toflow of the gases through the mixing valve.

Internal combustion engines are sometimes operated in plants where asupply of gas is not at all times available, for example, in plantswhere the gas used may be a lay-product of some manuwill factoringprocess. In such cases, it is desirable to operate the engine on liquidfuel, if gas is not available. By means of the mixing valve described,this can be easily done by moving the proportioning member 32 into theposition shown in Fig. 7 in which the gas supply is entirely interruptedand the air valve is wide open. In such cases, a carburetor C of anysuitable construction can then be attached to the air intake duct 10. Inorder to enable the proportioning valve member 32 to be quickly placedinto a position to operate on gas, when gas again becomes available,means are preferably provided to indicate when the proportioning member32 has been returned to its correct position. Any suitable means may beemployed for this purpose, and in the construction shown, the end covermember 28 is provided with a threaded aperture in which a bolt engages.When the proportioning member has been set into the correct position forthe particular gas on which the engine is to operate, this bolt 60 isturned until the end of the bolt engages the proportioning member 32 asshown in Fig. 6, whereupon the bolt is locked in this position by meansof a lock nut 61.

Consequently, when the proportioning member has been moved into theposition shown in Fig. 7, it can be quickly restored to the correctposition by turning the hand wheel 40 until the proportioning memberstrikes the stop bolt 60. The position of the proportioning member 32can also be determined by the end 62 of the screw 37, which occupiesdifferent positions of the proportioning member as may readily be seenby comparing the position of this end 62 in Figs. 6 and 7.

In order to provide for a more thorough mixing of the air and gas, thethrottle valve is preferably provided with a bafile 63, the lower end ofwhich is secured to or formed integrally with the semi-cylindricalportion 48 of the throttle valve at a point between the openings 56 and57 therein, and this bafile 63 preferably extends diagonally over theair opening 56. The baffle is provided with a relatively large apertureor central opening 64 through which the shaft 51 extends. This baffledivides the air entering into the mixing chamber so that a part of theair flows through the opening 64 therein and mixes with the gasimmediately after the gas enters the mixing chamber. Another part of theair is deflected by the baiile member 63 toward the upper portion andsides of the mixing valve, and then flows across the edge of the bafilein a direction more or less crosswise of the current of gas which hasbeen mixed with the primary current of air flowing through the opening64. By supplying the air to the gas in two streams mixing successivelywith the gas, or with different portions of the gas stream, a verythorough mixture of gas and air has been found to result, so that bettercombustion of the mixture takes place. A mixing baffle of this kind ispreferably, though not necessarily, used in connection with the mixingvalve.

The shaft 51 of the throttle valve, in the construction shown, isprovided at one end beyond the end or cover plate 2'7 with an arm 66suitably secured to the shaft, and a link 6'7 is shown pivotallyconnected with the outer end of this arm. This link may be actuatedthrough a bell crank lever 68, and another link 69 from any suitablecontrol device, such for example as a governor or a hand control, orboth governor and hand controls may be employed, which may bolt 71, andwhich has arms '72 and '73, one of 4 these arms, for example, the arm73, having an adjustable stop bolt 74 extending through a threaded holein the arm 73 and arranged to be locked in its adjusted position bymeans of a lock nut 75. The stop arm 72 and bolt 74 of the other arm 73are adapted to engage with opposite sides of a fixed stop projection 76,which, in the construction shown, is in the form of a lug or part formedon the end plate 28. Any other means for limiting the movement of thethrottle valve may beemployed.

In the operation of internal combustion engines from a source of gassupply by means of a mixing device of the kind shown, if the gas issupplied to the mixing valve under pressure, trouble is frequentlyexperienced in starting the engine because of too much gas accumulatingin the mixing valve and intake manifold because of the pressure of thegas. This results in a mixture which is too rich to ignite. Furthermore,with a valve of the kind shown, the pressure of the gas as Well as thequality of the gas, would have to be taken into consideration inadjusting the proportioning member 32. I have found that the operationof the mixing device can be simplified and made more satisfactory,particularly when the mixing valve is used in connection with aninternal combustion engine, if the gas is supplied to the mixing valveat not substantially more than atmospheric pressure. Under suchconditions, thesuction of the engine will draw into the mixing valveuniform proportions of air and gas, regardless of variations in suctionresulting from variations in engine speeds. For this purpose, a pressurereducing valve D is preferably employed, and which is so set or designedthat the pressure of the gas entering the reducing valve from the pipe18 is reduced to approximately atmospheric or subatmospheric pressurebefore passing into the supply reservoir or accumulator 1'7 Thisreducing valve may be of any suitable or usual construction, that shownin Fig. iihaving the usual housing provided with a passage 81 thereincontrolled by a valve 82 secured on a 86 through apertures 86a. and onits under surface by pressure in the receiver or cylinder 1'7 whichenters into the diaphragm chamber 86 through a small passage or duct 87.The under face of the diaphragm is acted upon by the pressure of the gasentering the regulator through the pipe 18. Any other pressure reducingmeans may be provided, if desired. 89 represents a gas shut-ofi cock inthe pipe 16.

When the engine is started, increased richness of the mixture may beobtained by manipulation of the choke valve 11, but excessively richmixtures are avoided because the pressure of the gas supplied to themixing valve is low. Preferably, the gas supplied at atmospheric orbelow atmospheric pressure, but pressures slightly exceeding atmosphericpressure may be used without departing from this invention. The gas.valve described has the advantage that it is easily adjustable, and hassuch a wide range of adjustment that it can be used in connection withany gas now available for operating an internal combustion engine,regardless of its quality, the adjustments ranging from equal parts ofair and gas to a zero quantity of gas when the parts are in the positionshown in Fig. '7. If the quality of the gas changes, it is an easymatter to adjust the mixing valve to operate on a different gas. Thearrangement of the proportioning member 32 and the throttle member issuch that adjustments of the proportioning member have no effect uponthe throttling member, so that any position of the throttling memberproduces the same throttling effect, regardless of the position of theproportioning member.

I claim as my invention:

1. A gas mixing valve, including a housing having gas inlet openingsformed therein, a member movable relatively to said housing and havingparts adapted to cooperate with said openings to decrease one of saidopenings while increasing the other opening, and a valve member movableto different positions with reference to said openings to simultaneouslyrestrict both of said openings to approximately the same extent.

a 2. A gas mixing valve, including a housing having gas inlet openingsformed in one side thereof and a gas discharge opening in another sidethereof, a member movable relatively to said housing and having openingstherein corresponding in size to said inlet openings, said openingsbeing spaced apart so that when one of said openings is infull'registration with an opening in said housing, the other opening insaid movable member substantially closes the other inlet opening in saidhousing, and a throttle member having openings adapted to registersimultaneously with said inlet openings in said housing and adjustablecrosswise of the direction of adjustment of said first mentioned memberfor throttling the passage of gases through said inlet openings. 3. Agas mixing valve, including a substantially cylindrical housing havinggas inlet openings formed in a side thereof and a gas outlet opening inanother side, a cylindrical member arranged Within said housing andadjustable therein and having opening registering with said outletopening, openings adapted to cooperate with said inlet openings in saidhousing and spaced so that adjustment of said mem her to decrease thepassage through one of said inlet openings results in increasing thepassage through the other opening, and a throttle member also arrangedwithin said housing and having a surface of cylindrical curvaturecooperating with the apertures of said housing and first mentionedmember for controlling the passage of gases through said openings.

4. A gas mixing valve, including a substantially cylindrical housinghaving gas inlet openings formed in a side thereof and a gas outletopening in the opposite side thereof, a cylindrical member arrangedwithin said housing and tdjustable lengthwise therein and having anopening registering with said outlet opening throughout all adjustmentsof said member and having openings adapted to cooperate with said inletopenings to change the proportions of the passages through said openingsrelatively to each other, and a throttle member arranged within saidhousing and of substantially semi-cylindrical form and cooperating withsaid inlet openings of said cylindrical member, whereby pressure of gasentering said opening tends to move said throttle member out of contactwith said cylindrical member.

5. In an air and gas mixing valve having separate inlet openings for airand gas, the combination of a throttle valve provided with openingsadapted to register with said inlet openings and having a part movablecrosswise of said inlet openings to throttle the same, a pivot aboutwhich said throttle member is movable, whereby suction within said valvetends to move said throttle member out of frictional contact with saidvalve.

6. A. gas mixing valve having a substantially cylindrical housingprovided with gas inlet openings in one portion thereof and a dischargeoutlet for a mixture of gases in another portion thereof, asubstantially cylindrical member arranged inside of said housing to movelengthwise therein and having air and gas openings adapted to cooperatewith said inlets in said housing to cover one of said inlets whileuncovering the other inlet, said member also having an opening inregistration with said outlet, means for adjusting said cylindricalmember lengthwise of said housing for varying the proportion of gasespassing through said inlets, a throttle valve of substantiallysemi-cylindrical form arranged within said cylindrical member andmovable crosswise thereof and having apertures arranged to register withsaid inlets in said housing for controlling the discharge of air and gasthrough said inlets. 7

7. A gas mixing valve having a substantially cylindrical housingprovided with gas inlet openings in one portion thereof and a dischargeoutlet for a mixture of gases in another portion thereof, asubstantially cylindrical member arranged inside of said housing to movelengthwise therein and having air and gas openings adapted to cooperatewith said inlets in said housing to cover one of said inlets whileuncovering the other inlet, said member also having an opening inregistration with said outlet, means for adjusting said cylindricalmember lengthwise of said housing for varying the proportion of gasespassing through said inlets, a

throttle valve of substantially semi-cylindrical form arranged withinsaid cylindrical member and movable crosswise thereof and havingapertures arranged to register with said inlets in said housing forcontrolling the discharge of air and gas through said inlets, and abattle on said throttle valve extending partially across one of saidinlet openings and having an aperture through which a part of one ofsaid gases can pass for mixing with the other gas, another part of saidfirst gas passing around the edgeof said bafiie.

3. A mixing valve having a substantially cylindrical housing providedwith gas inlet and outlet openings, a cylindrical proportioning memberslidable lengthwise within said housing for cooperating with said inletopenings to control the proportions of gases entering said housing, athrottle member arranged within said cylindrical member and having acylindrical portion provided with passages for throttling the flow ofgas through said housing, and cover members secured to said housing forclosing the ends thereof, a shaft journalled in said end cover membersand to which said throttle is secured, and means on said end covermember for regulating the position of said proportioning member Withinsaid housing.

9. A gas mixing valve, including a substantially cylindrical housinghaving gas inlet openings formed in a side thereof and a gas outletopening in the opposite side, a proportioning member cooperating withsaid inlet openings to vary the proportions of gases entering saidhousing, a throttle member within said housing and adjustable about anaxis in said housing, and having a part arranged to cooperate with saidproportioning member for controlling the quantity of gases entering saidhousing, said throttling member also having webs extending crosswise ofsaid cylindrical housing for directing the flow of gas toward saidoutlet opening.

10. A gas mixing valve including a housing having a cylindrical bore andhaving gas inlet openings formed therein, a cylindrical member arrangedin said housing and movable lengthwise therein and having parts adaptedto cooperate with said inlet openings to decrease one of said openingsWhile increasing the other opening, and a valve member also arranged insaid housing and movable approximately about the axis of saidcylindrical bore to different positions with reference to said, openingsto simultaneously vary the discharge of gas through both or" saidopenings.

11. A valve for use with either gaseous or liquid fuel, including ahousing having air and gas inlet openings formed in a side thereof, aproportioning member cooperating with said inlet openings to vary theproportions of air and gas entering said housing and arranged toentirely close said gas inlet openingtwhen said air inlet opening isWide open, a single throttle member cooperating with both of said inletopenings for simultaneously restricting both of said openings, and meansfor connecting a liquid fuel carburetor with said air inlet opening,whereby said throttle member serves to control combustible mixtures ofother gaseous or liquid fuel.

ELWOOD T. LARKIN.

